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Mass finishing is a term used to describe a group of abrasive industrial processes by which large lots of parts or components made from metal or other materials can be economically processed in bulk. This processing is performed to achieve one or several of a variety of edge and surface effects. These include deburring, descaling, surface smoothing, edge-break, radius formation, removal of surface contaminants from heat treat and other processes, pre=plate, prepaint or coating surface preparation, blending in surface irregularities from machining or fabricating operations, producing reflective surfaces with nonabrasive burnishing media, refining surfaces, and developing super-finish or micro-finish equivalent surface profiles.

All mass finishing processes utilize a loose or free abrasive material referred to as media within a container or chamber of some sort. Energy is imparted to the abrasive media mass by a variety of means to impart motion to it and to cause it to rub or wear away at part surfaces.

Some Case Studies — Edge and surface finishing for improved performance and fatigue failure resistance: The technical literature is replete with examples of case studies indicating that substantial fatigue resistance can be developed with mass finishing methods such as barrel finishing. One study published by Iron Age magazine back in 1959 documented studies on the compressive stresses to be developed with various types of abrasive and non-abrasive media in tumbling barrels. Some processes are especially well known for this characteristic. Steel media or ball burnishing processes using vibratory techniques are known not only for producing aesthetically pleasing surfaces, but also enhancing service life of components because of the bulk-density of the media itself (300 lb./ft3 as compared to 80 to 100 lb./cu. Ft3 with typical abrasive ceramic media types). Some promising research has been done by major aerospace companies that indicate large air frame components can be processed to enhance fatigue life, and that fatigue life of components stressed or weakened in service can be improved during overhaul cycles as well.

[ABOVE: Isotropic Micro-Finished Part photography by Mark Riley, BV Products] Dave Davidson is with SME Manufacturing and an advisor to the Machining/Material Removal Technical Community; he can be reached at dryfinish@gmail.com. Jack Clark, also an SME member, is with the Colorado State University’s Department of Mechanical Engineering and with Surface Analytics, LLC; he can be reached […]

In the most recent data, manufacturers contributed $2.18 trillion to the U.S. economy in 2016. This figure has risen since the second quarter of 2009, when manufacturers contributed $1.70 trillion. Over that same time frame, value-added output from durable goods manufacturing grew from $0.87 trillion to $1.20 trillion, with nondurable goods output up from $0.85 trillion […]

Slides are also shown in the gallery below, in order to enlarge a particular slide, click on the image. [Note: Click on any image above to enlarge to full-screen view] [Note 2: Processing videos can be seen at the bottom of this page] Additional Information on Centrifugal Isotropic Finishing Centrifugal barrel finishing (CBF) […]

To make arrangements for free sample finishing of your parts contact: Dave Davidson | Deburring/Finishing Specialist | dryfinish@gmail.com Below are a series of operational videos demonstrating the operations of larger high-speed centrifugal finishing equipment. This method has been shown to process parts 10X faster than conventional tumbling or vibratory finishing processes. It is also capable […]

Centrifugal Isotropic Finishing has been shown to be useful in reducing the rough surfaces common to 3D printed parts. Below is an example of surface finishes that can be achieved with the method. The slides provide profilomic and areal data tabulated by Jack Clark, President of Surface Analytics. This work was performed by Jack for a study being made by SME’s Machining/Material Removal Technical Community. The slides show surface readings from a part pictured above as printed, and then following centrifugal isotropic finishing. The measurements were made in both 2D and 3D. To summarize, in this test, surface roughness was reduced from 356.24µin Ra. to 12.06µin Ra.

Turbo-Abrasive Machining (TAM) is a new process for deburring and surface conditioning sophisticated multi-axis machined parts. Many parts, because of size and shape factors, can not be finished by a mass media technique but need manual intervention for final abrasive finishing. Apart from safety and production line/time considerations, a significant disadvantage of manual deburring is its impact on quality control and assurance procedures, which have often been computerized at great cost. The TAM process addresses these problems by automating the final machining and finishing production steps.

In TAM, fluidized bed technology is utilized to suspend abrasive or even peening materials in a specially designed chamber: Part surfaces are exposed to and interact with the fluidized bed materials on a continuous basis by high speed rotational or oscillational motion in an entirely dry environment.

The combination of abrasive envelopment and high speed rotating contact can produce important functional metal surface conditioning effects and deburring and radius formation very rapidly. Because abrasive operations are performed on all parts of rotating components simultaneously, the part and feature uniformities achieved are very hard to duplicate by other methods. In addition, sophisticated computer control technologies can be applied to create processes tailored for particular parts.

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ABOVE: Some examples of Turbo-Finish and Turbo-Abrasive Machining Processing

Although the abrasive materials used for TAM processing are in some ways similar to grinding and blasting materials, the surface condition produced is unique. One reason for this is the multi-directional and rolling nature of abrasive particle or peening particle contact with part surfaces. Surfaces are characterized by a homogenous, finely blended abrasive pattern developed by the non-perpendicular nature of abrasive attack.

There is no perceptible temperature shift in the contact area and the micrto-textured random abrasive pattern is a highly attractive substrate for subsequent coating operations. In addition to the foregoing, the process has additional advantage, in that it develops significant beneficial compressive stress and stress equilibrium in parts as well as edge and surface finish conditions that are isotropic, plateaued or planarized surface characteristics and have negatively or neutrally skewed low micro-inch surface profiles.

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dryfinish

I am a deburring and surface finishing specialist, consultant and advisor to SME's [Society of Manufacturing Engineers] Technical Community Network. The focus of my activity is assisting manufacturers and machine shops with reducing their dependence on hand or manual deburring and finishing methods, and helping them to upgrade the edge and surface finish quality of their parts.
I currently work from Colville, WA but I assist clients nation-wide. I can arrange for free sample processing and process development for your challenging deburring and finishing needs and can provide you with either contract finishing services or the in-house capability to produce improved hands-free finishes on precision parts. I can be contacted at 509.230.6821 or dryfinish@gmail.com. Let me know if I can be helpful.
https://dryfinish.wordpress.com
* 2014 - 2017 Advisor: SME Manufacturing - Machining/Material Removal Technical Community
* 2007 Chair: Chapter 248; Spokane WA, 2010 Certification Chair; 2010 Networking Coordinator at Society of Manufacturing Engineers
* 2010 Co-Chair - Machining and Material Removal Technical Community at Society of Manufacturing Engineers: Deburr/Finish Tech Group; Consultant: Deburring Solutions
* Vice-President: Turbo-Finish Corporation
* Chair: Mass Finishing Job Shops Association
* Vice President: PEGCO Process Laboratories
View all posts by dryfinish

Turbo-Abrasive Machining (TAM) is a new process for deburring and surface conditioning sophisticated multi-axis machined parts. Many parts, because of size and shape factors, can not be finished by a mass media technique but need manual intervention for final abrasive finishing. Apart from safety and production line/time considerations, a significant disadvantage of manual deburring is its impact on quality control and assurance procedures, which have often been computerized at great cost. The TAM process addresses these problems by automating the final machining and finishing production steps.